The rise of international travel has given previously region-specific diseases a global presence. The book is aimed at students, interns, fellows and health care providers.It contains chapters devoted to clinical examination and an outline of how to approach common problems encountered at the bedside. The format and style of the book allows common clinical problems to be identified and recognised within the framework of a global perspective. More info: http://www.mcgraw-hill.com.au/html/9780070285576.html

1. Gastroenterology
and Hepatology
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Manual
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A Clinician’s Guide
to a Global Phenomenon
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C.S. Pitchumoni
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Joseph Sung
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2. Gastroenterology and
Hepatology Manual
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3. ii CONTENTS
Dedication
Professor Segal
To my wife Arlene for her unstinting devotion and
to my dear children Rosh, Perry, Hadass and their families
for their continuing understanding and support.
Professor Pitchumoni
To my wife Prema Pitchumoni and to all my students
Professor Sung
To members of the GI team at Prince of Wales Hospital
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4. Gastroenterology and
Hepatology Manual
A Clinician’s Guide
to a Global Phenomenon
Isidor Segal
C.S. Pitchumoni
Joseph Sung
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5. Notice
Medicine is an ever-changing science. As new research and clinical experience broaden our knowledge,
changes in treatment and drug therapy are required. The editors and the publisher of this work have
checked with sources believed to be reliable in their efforts to provide information that is complete
and generally in accord with the standards accepted at the time of publication. However, in view of
the possibility of human error or changes in medical sciences, neither the editors, nor the publisher,
nor any other party who has been involved in the preparation or publication of this work warrants that
the information contained herein is in every respect accurate or complete. Readers are encouraged to
confirm the information contained herein with other sources. For example, and in particular, readers
are advised to check the product information sheet included in the package of each drug they plan
to administer to be certain that the information contained in this book is accurate and that changes
have not been made in the recommended dose or in the contraindications for administration. This
recommendation is of particular importance in connection with new or infrequently used drugs.
First published 2011
Text © 2011 McGraw-Hill Australia Pty Ltd
Illustrations and design © 2011 McGraw-Hill Australia Pty Ltd
Additional owners of copyright are acknowledged in on-page credits.
Every effort has been made to trace and acknowledge copyrighted material. The authors and publishers
tender their apologies should any infringement have occurred.
Reproduction and communication for educational purposes
The Australian Copyright Act 1968 (the Act) allows a maximum of one chapter or 10% of the pages of this
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Enquiries should be made to the publisher via www.mcgraw-hill.com.au or marked for the attention of
the permissions editor at the address below.
National Library of Australia Cataloguing-in-Publication Data
Author: Segal, Isidor.
Title: Gastroenterology and hepatology manual : a clinician’s
guide to a global phenomenon / Isidor Segal, C.S. Pitchumoni, Joseph Sung.
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ISBN: 9780070285576 (pbk.)
Notes: Includes index.
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Subjects: Gastroenterology--Handbooks, manuals, etc.
Other Authors/Contributors: Pitchumoni, C.S., Sung, Joseph.
Dewey Number: 616.33
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Published in Australia by
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McGraw-Hill Australia Pty Ltd
Level 2, 82 Waterloo Road, North Ryde NSW 2113
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Acquisitions editor: Elizabeth Walton
Associate editor: Fiona Richardson
Art direction and cover design: Astred Hicks
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Internal design: Peta Nugent
Senior production editor: Yani Silvana
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Permissions editor: Haidi Bernhardt
Copy editor: Ross Blackwood
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Proofreader: Anne Savage
Indexer: Russell Brooks
Typeset in Zapf Humanist 601 BT, 8/10.5 by Mukesh Technologies, India
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Printed in China on 80gsm matt art by iBook Printing Ltd

6. Foreword
Rapid globalisation is affecting all aspects of life, and the practice of medicine
is no exception. Gastroenterology and Hepatology: a Clinician’s Guide to a
Global Phenomenon is a thoughtful attempt to address the issues related to
the teaching and clinical practice of gastroenterology and hepatology in the
current climate. The book is creatively organised and the chapters have been
written by a team of international experts in the field.
Gastroenterology and Hepatology contains carefully selected topics
that are of particular importance to the practice of gastroenterology and
hepatology throughout the world. Chapter 1, for example, provides a
scholarly, coherent discussion of the underlying factors that are propelling
the development of diseases that are similar worldwide, and of the evolution
from regional to global medicine, particularly in the field of gastroenterology
and hepatology.
The popularity of international travel has resulted in travellers being
exposed to new gastrointestinal and liver disorders that are not present in
their homelands. The chapters devoted to international travel medicine
provide useful information on the diagnosis and management of
gastrointestinal and liver disorders both for travellers from different parts of
the world to a common destination and for travellers from one region to
varied regions.
The editors have cleverly divided clinical gastrointestinal and liver
disorders into groups, such as diseases that are common in West but seem
to spreading to the East, diseases that are common in emerging countries
and spreading globally, and diseases that represent the melting pot. Other
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chapters discuss diseases—including gastrointestinal and liver cancers—that
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have different epidemiology, pathophysiology and clinical behaviour in
different parts of the world.
Chapters discussing gastrointestinal and hepatic disorders of global
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importance include: one on the differences in the diagnostic tools that are
used by practitioners for diagnosis and management of the same disorders in
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different parts of the globe; chapters dealing with important liver disorders
of international interest because of the diversity of their epidemiology and
clinical presentation; and chapters on biliary and pancreatic disorders that
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discuss global diversity in epidemiology, aetiology, clinical manifestations and
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management of these disorders.
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Finally, the book includes a chapter on Chinese traditional medicine and
another on Indian traditional medicine, both focused on gastrointestinal and
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7. vi FOREWORD
liver diseases. Throughout the world, the vast majority of these diseases are
being treated with alternatives to conventional medicine practised in the
West. Moreover, many of the practitioners of alternative forms of medicine
are now also formally trained in Western medicine. This understanding of
different types of therapies will no doubt be beneficial for patients.
This unique compilation, written by talented, scholarly contributors
with expertise in international medicine, is a pioneering work in global
gastroenterology and hepatology. Students and practitioners who care for
patients in the global environment will find this book very useful.
Raj K. Goyal, MD
Mallinckrodt Professor of Medicine
Harvard Medical School
VA Boston Health Care
Boston, Massachusetts 02132
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8. Contents
Foreword v
About the editors x
About the contributors xi
Acknowledgments xvi
Section 1: An overview 1
Chapter 01 • Introduction 2
Chapter 02 • A global phenomenon: medicine without 4
frontiers
Section 2: Gastrointestinal diseases 13
Part A: Clinical assessments 14
Chapter 03 • Acute and chronic abdominal pain 14
Part B: Western diseases spreading their wings 26
Chapter 04 • Gastro-oesophageal reflux disease (GERD) 26
Chapter 05 • Irritable bowel syndrome 39
Chapter 06 • Changing patterns of inflammatory bowel disease 48
in a global context (ulcerative colitis)
Chapter 07 • Changing patterns of inflammatory bowel disease 66
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in a global context (Crohn’s disease)
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Chapter 08 • Constipation 77
Chapter 09 • Colorectal cancer 92
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Part C: Diseases of emerging countries making inroads globally 100
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Chapter 10 • Gastrointestinal tuberculosis versus Crohn’s 100
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disease
Chapter 11 • Traveller’s diarrhoea 114
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Chapter 12 • Cholera 126
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Chapter 13 • Malaria 139
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Chapter 14 • Leptospirosis 156
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9. viii CONTENTS
Chapter 15 • Listeriosis 163
Chapter 16 • Amoebiasis 171
Chapter 17 • Schistosomiasis: global impact 181
Part D: Diseases in the melting pot 191
Chapter 18 • Giardiasis, cryptosporidiosis and cyclosporiasis 191
Chapter 19 • Gastrointestinal disorders in HIV infection 197
and other sexually transmitted infections
Par t E: Cancers of the gastrointestinal tract 207
Chapter 20 • Cancer of the oesophagus: intercontinental 207
variations
Chapter 21 • Global trends in gastric cancer: association with 217
Helicobacter pylori and other factors
Chapter 22 • Clinical aspects of gastric cancer 223
Part F: Preventative gastroenterology 227
Chapter 23 • Preventative gastroenterology 227
Part G: Nutrition 242
Chapter 24 • Nutritional evaluation: a paradigm shift in the 242
twenty-first century
Chapter 25 • Impact on children of global nutritional 257
breakdown
Part H: Gastrointestinal tools 270
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Chapter 26 • Gastrointestinal bleeding 270
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Chapter 27 • Gastrointestinal endoscopy: an overview 280
Chapter 28 • Alimentary tract imaging 292
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Section 3: Pancreatic diseases 303
Chapter 29 • Acute pancreatitis 304
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Chapter 30 • Chronic pancreatitis 316
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Chapter 31 • Pancreatic cancer 328
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Chapter 32 • Imaging of the pancreas 335
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10. CONTENTS ix
Section 4: Hepatology 347
Part A: Diseases evoking a global impact 348
Chapter 33 • Cirrhosis and complications 348
Chapter 34 • Acute liver failure 369
Chapter 35 • Acute hepatitis 381
Chapter 36 • Hepatitis B infection 394
Chapter 37 • Hepatitis C infection 409
Chapter 38 • Non-alcoholic fatty liver disease 422
Chapter 39 • Alcoholic liver disease 437
Chapter 40 • Hepatocellular carcinoma 444
Chapter 41 • Hepatic imaging 453
Part B: Biliary diseases 465
Chapter 42 • Gallstones and their sequelae 465
Chapter 43 • Neoplasms of the gall bladder and biliary tracts 475
Chapter 44 • Imaging of biliary tracts 489
Section 5: Traditional cultural medicine 499
Chapter 45 • Traditional Chinese medicine 500
Chapter 46 • Traditional Indian medicine 514
Index 526
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11. About the editors
Isidor Segal FRACP, FRCP (UK), AGAF, Master World
Gastroenterology Organisation (WGO)
Professor Segal established the African Institute of Digestive Diseases in
1999. The model of this institute has been used by the WGO to establish
13 training centres in countries such as Morocco, Pakistan, Bangkok, Egypt,
Chile, Bolivia and Argentina.
Professor Segal has held many positions in the WGO, including: member
of the Education and Training Committee and Vice Chairman African and
Middle East Zone. He has published more than 200 papers and has recently
co-edited two books and is a visiting lecturer at universities around the world.
He is currently working in the Gastroenterology Division at Prince of Wales
Hospital, Sydney.
C.S. Pitchumoni MD, MACP, MACG, AGAF, MPH
Professor Pitchumoni is the Adjunct Professor of Medicine at New York
Medical College, Clinical Professor of Medicine at both Robert Wood
Johnson School of Medicine at New Brunswick, New Jersey, and at
Drexel University in Philadelphia, USA. Currently he is also Chief of
Gastroenterology, Hepatology and Clinical Nutrition at Saint Peter’s
University Hospital in New Brunswick.
Professor Pitchumoni has more than 40 years of teaching and research
experience as a clinical gastroenterologist.
Joseph Sung MD, PhD
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Professor Sung is the President of the Chinese University of Hong Kong
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(CUHK) and Mok Hing Yiu Professor of Medicine. Before this appointment,
he was Director of the Institute of Digestive Disease, Chairman of the
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Department of Medicine and Therapeutics, and Associate Dean of Medicine
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at CUHK. He is a gastroenterologist with special interest in gastrointestinal
bleeding, digestive cancer and hepatitis infection. He has published more
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than 650 full papers in scientific journals and edited or co-edited seven
books.
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12. About the contributors
M. Abdullah, Indonesia
Division of Gastroenterology, Department of Internal Medicine, Faculty of
Medicine, University of Indonesia, Jakarta.
R.M. Agrawal, USA
Associate Professor of Medicine, Drexel University College of Medicine,
Philadelphia.
Associate Clinical Chief, Research and Education, Division of
Gastroenterology, Hepatology and Nutrition, Department of Medicine,
Allegheny General Hospital, Pittsburgh.
D.V. Alcid, USA
Professor of Medicine and Pathology, University of Medicine and Dentistry,
Robert Wood Johnson Medical School, New Brunswick, New Jersey.
Director, Microbiology Laboratory, St. Peter’s University Hospital,
New Brunswick, New Jersey.
D. Amarapurkar, India
Bombay Hospital and Medical Research Centre; Mumbai and Jagjivanram
Western Railway Hospital, Mumbai.
T.L. Ang, Singapore
Department of Gastroenterology, Changi General Hospital.
R. Banerjee, India
Consultant Gastroenterologist, Asian Institute of Gastroenterology,
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Hyderabad, Andhra Pradesh.
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Z. Bian, Hong Kong, China
School of Chinese Medicine, Hong Kong Baptist University.
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M. Bilal, USA
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University of Tennessee Health Science Center, Memphis.
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P. Chang, Australia
Gastroenterology Division, Prince of Wales Hospital, Sydney.
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J. Chaganti, Australia
Senior Lecturer in Radiology, University of New South Wales, Sydney.
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Senior Consultant, Radiology, St Vincent’s Hospital, Sydney.
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13. XII ABOUT THE CONTRIBUTORS
G.M. Dusheiko, England
Professor of Medicine, Centre for Hepatology, Royal Free Hospital and
University College London Medical School.
S.S. Fedail, Sudan
Consultant Physician and Gastroenterologist, Chairman, Fedail Hospital,
Khartown.
K.M. Fock, Singapore
Department of Gastroenterology, Changi General Hospital.
A.Y. Garcia, Cuba
Department of Gastroenterology, National Institute of Gastroenterology,
Havana.
K.L. Goh, Malaysia
Professor of Medicine, Head of Gastroenterology and Hepatology, University
of Malaya, Kuala Lumpur.
E.V. Gomez, Cuba
Director of Research, National Institute of Gastroenterology, Havana.
R. Jackson, Australia
Paediatric Gastroenterologist, Prince Of Wales Private Hospital, Sydney.
S.S. Jhangiani, USA
Attending, Departments of Internal Medicine, Gastroenterology and Clinical
Nutrition, Montefiore Medical Center, New York.
Assistant Professor of Medicine, New York Medical College, Valhalla, New York.
Founder and Chairman, www.NutritionVista.com.
Founder and Chairman, Doctors for a Healthier Bronx.
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J.C. Joshi, India
Consulting Gastroenterologist and Hepatologist, Samvedana Clinic, Jolly
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Centre, Mumbai.
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A. Karstaedt, South Africa
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Division of Infectious Diseases, Department of Medicine, Chris Hani
Baragwanath Hospital and the University of the Witwatersrand,
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Johannesburg.
S.R. Lin, China
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Peking University Third Hospital, Peking.
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S. Nair, USA
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Professor of Medicine, Medical Director of Liver Transplantation, University
of Tennessee Health Science Center, Memphis.
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14. ABOUT THE CONTRIBUTORS XIII
C.J. Ooi, Singapore
Head and Senior Consultant, Department of Gastroenterology and
Hepatology, Director, Inflammatory Bowel Disease Centre, Singapore
General Hospital.
Associate Professor, Duke-NUS Graduate Medical School.
Clinical Associate Professor, Yong Loo Lin School of Medicine, NUS.
H. Paradwala, India
Consulting Physician, Saifee Hospital and Prince Aly Khan Hospital, Mumbai.
N.Y. Pathak, India
Senior Research Fellow, Medical Research Centre, Kasturba Health Society,
Mumbai.
C.S. Pitchumoni, USA
Clinical Professor of Medicine, Robert Wood Johnson School of Medicine,
New Brunswick, New Jersey.
Chief of Gastroenterology, Hepatology and Clinical Nutrition, Saint Peter’s
University Hospital, New Brunswick, New Jersey.
A.A. Rani, Indonesia
Head, Division of Gastroenterology, Department of Internal Medicine,
Faculty of Medicine, University of Indonesia, Jakarta.
D.N. Reddy, India
Chairman, Chief Gastroenterologist, Asian Institute of Gastroenterology,
Hyderabad, Andhra Pradesh.
S. Riordan, Australia
Professor of Medicine, Head of Department of Gastroenterology and
Hepatology, Prince of Wales Hospital and the University of New South
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Wales, Sydney.
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S.K. Sarin, India
Professor and Head of Department of Hepatology, Institute of Liver and
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Biliary Sciences, New Delhi.
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I. Segal, Australia
Gastroenterology Division, Prince of Wales Hospital, Sydney.
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S. Shah, India
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Previous Head of Department of Gastroenterology, Sir J.J. Hospital, and
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Grant Medical College Honorary Gastroenterologist at Jaslok, Saifee and
Breach Candy Hospital, Mumbai.
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15. XIV ABOUT THE CONTRIBUTORS
P. Sharma, India
Assistant Professor, Department of Hepatology, Institute of Liver and Biliary
Sciences, New Delhi.
O. Shrivsatav, India
Consultant, Infectious Diseases and HIV Medicine, Sir H.N. Hospital, Jaslok
Hospital, Saifee Hospital, Specialty Clinics, Breach Candy Hospital, Unit
Head, Kasturba Hospital for Communicable Diseases, Mumbai.
D. Singhal, India
Department of Gastroenterology and Gastrointestinal Surgery, Pushpawati
Singhania Research Unit for Liver, Renal and Digestive Diseases, New Delhi.
E.A. Soler, Cuba
General Director, National Institute of Gastroenterology, Havana.
J.D. Sollano, Philippines
Professor of Medicine, University of Santo Tomas, Manilla.
J. Sung, Hong Kong, China
President of the Chinese University of Hong Kong (CUHK) and Mok Hing Yiu
Professor of Medicine.
R.K. Tandon, India
Department of Gastroenterology and Gastrointestinal Surgery, Pushpawati
Singhania Research Unit for Liver, Renal and Digestive Diseases, New Delhi.
S. Tejavanija, Thailand
Medical Staff, Department of Endocrinology and Clinical Nutrition,
Phramongkutklao Hospital, Bangkok.
K.T. Thia, Singapore
Consultant, Gastroenterology and Hepatology, Inflammatory Bowel Disease
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Centre, Singapore General Hospital.
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R. Toney, USA
Senior Gastroenterology Fellow, Allegheny General Hospital, Drexel
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University College, Division of Gastroenterology, Hepatology and Nutrition,
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Department of Medicine, Pittsburgh.
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J. Tu, Australia
Clinical Research Fellow, Gastrointestinal and Liver unit, Prince of Wales
Hospital, Sydney.
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A.D.B. Vaidya, India
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Research Director, ICMR Advanced Centre of Reverse Pharmacology in
Traditional Medicine, Medical Research Centre, Kasturba Health Society,
Mumbai.
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16. ABOUT THE CONTRIBUTORS XV
S.W. Wong, Australia
Senior Lecturer, Colorectal Surgeon, Prince of Wales Hospital, University of
New South Wales, Sydney.
J.C.Y. Wu, Hong Kong, China
Professor, Institute of Digestive Disease, Chinese University of Hong Kong.
S.D. Xiao, China
Shanghai Renji Hospital, Shanghai Jiaotong, University School of Medicine,
Shanghai Institute of Digestive Diseases, Shanghai.
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17. Acknowledgments
Gastroenterology and hepatology continue to progress at an accelerating
pace. Exciting new advances in techniques, treatments, diagnostic strategies
and positive research outcomes have resulted in a new world for medical
practitioners.
A silent ripple has spread like a global tsunami that has made a term like
‘Western diseases’ obsolete. Obesity, inflammatory bowel disease, gastro-
oesophageal-reflux disease, colorectal cancer and other Western diseases are
now common in the burgeoning emerging populations of India, China and
other Asian and Pacific rim countries.
We have been fortunate to have the commitment of internationally
renowned experts from around the world to address the global presentation
of these diseases in their various geographic regions. These invited
contributors are at the cutting edge of both research and clinical aspects of
gastroenterology and hepatology and are able to provide an unprecedented
insight into the global phenomena of the diseases.
The editors are honoured by the excellence of the work of these
international authors, who have been partners in a sometimes difficult
process. They have generously continued to give their time and energy in
order to ensure the success of the book.
We believe the book may serve to bridge current knowledge for students,
trainees, medical practitioners and researchers in digestive diseases.
The format of the publication facilitates ease of access to the specific
information required by users. In addition to the core text, chapters also
include key points, tables, summaries and recommended reading.
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The editors are enormously indebted to the dedicated team at McGraw-
Hill for their guidance, patience and zest in getting the book to press. In
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particular we are very grateful to Fiona Richardson, who was the driving force
behind the scenes and who encouraged the enthusiastic participation of the
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other team members. We are most grateful to Lizzy Walton, Ross Blackwood
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and Yani Silvana for being part of this creative team and for their professional
interest in the provision of a distinctive book.
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Isidor Segal, C.S. Pitchumoni and Joseph Sung
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18. Chapter 2: A global
phenomenon: medicine
without frontiers
I. Segal (Australia)
Key points
Climate change.
Urbanisation.
Xenobiotics: smoking, alcohol, volatile hydrocarbons, occupational
disease, exposure to low-dose ionising radiation and air pollution.
Dietary changes: obesity and junk food.
Exercise trends.
Introduction
This is perhaps the most beautiful time in human history; it is really pregnant with
all kinds of creative possibilities made possible by science and technology which
now constitute the slave of man—if man is not enslaved by it.
Dr Jonas Salk (1914–1995), developer of the polio vaccine.
Globalisation has shifted the course of medicine. There are no longer any
sharp divisions between geographical regions in terms of the prevalence and
types of disease to be found in them: it is becoming more difficult to label
diseases in terms of their geographic location. Environmental, economic,
technological and social changes are evolving so rapidly in the twenty-first
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century that a paradigm shift is needed in order to categorise diseases that
previously were restricted by geographical location.
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The following discussion focuses on factors contributing to these
changes: climate change, urbanisation, xenobiotics, dietary changes and
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exercise trends.
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Climate change
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The dynamics of disease patterns are changing due to climate change.
In many places the Earth’s temperature is rising; some have predicted that the
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average global temperature will rise by 3 to 7 degrees by 2100.
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Warming is escalating, and significant rises have occurred in recent
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decades. Human activities enhance the natural greenhouse effect by
generating greenhouse gases that trap heat in the atmosphere. If this
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19. CHAPTER 2: A GLOBAL PHENOMENON: MEDICINE WITHOUT FRONTIERS 5
continues at or above the current rate, average global temperatures are
predicted to continue to rise, bringing significant long-term effects for people,
the environment and disease patterns.
Burning fossil fuels such as coal, natural gas and oil for powering factories,
industrial plants, home environments and cars, along with continued
tree-clearing for extended building development as populations increase, K
CK FLIC
all exacerbate greenhouse gas problems.1
Health conditions are most susceptible to changes in climate, particularly 2
in the very young, the very old or those with heart and respiratory problems.
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Change also affects microbial contamination pathways and transmission
mechanisms such that water-borne, food-borne, rodent-borne and
vector-borne diseases increase, especially malaria and diarrhoeal diseases.
If temperatures rise 2 to 3 degrees Celsius by 2030, as some predictions
maintain, the risk of malaria would increase by between 3 and 5 per cent
and diarrhoeal diseases would increase by 10 per cent. The latter would
particularly affect children, among whom mortality and morbidity from
diarrhoea is already high in some developing countries. An example of this
is seen in the spread of malaria to the previously malaria-free region of the
Eastern Highlands of Kenya, where warmer, wetter weather has resulted in
high rates of illness and death.2
McMichael et al. cite the known and probable health hazards of climate
variability and health change. They include temperature extremes, more
daily death events and disease events due mainly to very hot days and the
effects of floods, with more injuries, deaths and resultant infectious diseases,
mental health disorders, increased allergic disorders and greater risk of
diarrhoeal diseases, especially salmonellosis (poisoning by contaminated
food).3
The risk of water-borne infections such as cholera may increase, and the
incidence of mosquito-borne infections tends to increase with warming and
changes in rainfall; similarly, tick-borne infections may increase.
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Recent climate change has already contributed to altered food yields in
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some regions, causing changes in temperature, rainfall, soil moisture, pest
activity and plant disease that have reduced food production and increased
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the risk of malnutrition. It is evident that swift and aggressive international
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action is required to deal with the situation.
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Urbanisation
Asia is the most rapidly urbanising continent. Between 1970 and 1990
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the world’s urban population rose by 1038 million, of which Asian cities
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accounted for 589 million (56%). At the current rate, in China 870 million
people—more than half the projected population—will be living in cities
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within less than a decade.4
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20. 6 SECTION 1 | AN OVERVIEW
In 2008 the proportion of the world’s population living in urban areas
crossed the 50 per cent mark. Most observers believe that essentially all
population growth from now on will be in cities. The transition is happening
chaotically, resulting in unorganised urban landscapes in which many of
the poorest people are rapidly absorbed into urban slums. Urbanisation is a
health hazard for certain vulnerable populations, and this demographic shift
threatens to create a humanitarian disaster. The threat comes both in the
form of rising rates of endemic disease and a greater potential for epidemics
and even pandemics.
Most people who relocate to cities are in search of employment. Many
find that their only option is to live in dense, unplanned, illegal settlements
lacking basic public infrastructure. These slums make up an increasing
proportion of some growing cities. Increased population density in urban
areas that lack proper water supply and sanitation magnifies the risk of
communicable diseases being transmitted. Poor urban areas readily become
breeding grounds for emerging infections and potential pandemics. Although
slum residents may live close to health care providers, they generally have
little access to high-quality care. Fundamental public health-related services,
such as a safe water supply, sanitation and oral rehydration therapy, remain
important. As the world becomes increasingly urban, the health of the urban
poor may suffer and the stage could be set for devastating pandemics of
infectious disease.5
In addition to these growing problems, rapid and unplanned urbanisation
has important ramifications with regard to urban pollution and health due to
inadequate drainage and solid waste services, poor urban and industrial waste
management, air pollution (especially from particulates) and overcrowding,
as well as such factors as depletion of water and forest resources.
Asia’s economic growth is expected to continue. In order to achieve
sustainable development there will be an enormous need for waste
disposal facilities, roads, ports, power plants, water mains, airports and
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communication systems. The issue of access is important and the cost of
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infrastucture will be trillions of dollars.
The quality of education among the marginalised poor is variable and
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generally of a low standard. Access to health care is also low in poorer areas
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with overcrowded poor-quality housing, lacking potable water and with
substandard sanitation.
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In sub-Saharan Africa the traditional rural population is rapidly moving to
cities; more than half of the population of approximately 700 million already
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live in urban areas.
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UN-Habitat, the United Nations Human Settlements Program, has stated
that Africa’s chaotic urbanisation, together with the HIV/AIDS pandemic,
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was the biggest threat to the world’s poorest continent. It was estimated that,
by 2000, 51 per cent of Africans would be living in cities and towns, and
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21. CHAPTER 2: A GLOBAL PHENOMENON: MEDICINE WITHOUT FRONTIERS 7
Africa would cease to be a rural continent. In the more developed countries,
84 per cent of the inhabitants will be urban dwellers by 2030.6
In agreement with this, according to a new report issued by the United
Nations Population Division, virtually all population growth expected in the
next 30 years will be concentrated in urban areas. By 2030 the worldwide
population living in urban areas is projected to reach 60 per cent.7 K
CK FLIC
Xenobiotics 2
Xenobiotics are substances foreign to living systems. The term includes drugs,
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pesticides, pollutants, carcinogens, volatile petrochemicals, food additives
and polluted working environments. The following discussion focuses on
some of the important xenobiotics.
Smoking
Smoking is a risk factor for many diseases. Lung cancer is the most serious,
but other lung conditions such as chronic airways disease and emphysema
are also related to smoking, which has been identified as the second most
important risk factor for death from any cause worldwide. China, with a
population of 1.3 billion, is the world’s largest producer and consumer
of tobacco and a large proportion of deaths in China are attributable to
smoking.
It had also been predicted that smoking would cause approximately
930 000 adult deaths in India by 2010, mainly from tuberculosis and
respiratory disease in both men and women, and from heart disease and
cancer in men.
The three leading causes of death attributable to smoking in the
United States are cancer, cardiovascular disease and respiratory disease in
men and respiratory disease in women.8
Alcohol
Alcohol abuse causes 3.5 per cent of all deaths and disability in the world,
ly
and its impact is more than five times as significant as illegal drugs on
on
human health globally.9
Alcohol consumption in South-East Asia is rising, particularly among
s
youths and young adults in both rural and urban areas. This may be due to
ge
economic growth, increasing trade liberalisation and globalisation. Many
countries in Asia, including India, Sri Lanka, Malaysia and Thailand, cannot
pa
provide accurate consumption figures since local cheap illicit brews are
consumed in unknown quantities.10
e
It is common knowledge that alcohol leads to health-related and social
pl
problems. In the digestive system alcohol is a leading cause of cirrhosis and
pancreatitis and is also related to cancers of the mouth, oropharyngeal,
am
esophageal, liver and colorectal cancer. Diabetes is also implicated in the
disease pattern.
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22. 8 SECTION 1 | AN OVERVIEW
Volatile hydrocarbons
A 1998 study carried out in Soweto, South Africa, suggested that exposure
to volatile hydrocarbons, particularly petrochemicals, increases susceptibility
to pancreatitis.11 Braganza et al. had also earlier suggested that occupational
exposure to volatile hydrocarbons may be related to idiopathic and alcohol-
related pancreatitis.12
Chronic exposure to xenobiotics such as smoke from coal fires and
kerosene fumes from Primus stoves, along with long-term alcohol abuse
and smoking, were cited as major contributing causes of pancreatitis. Both
acute and chronic pancreatitis appear to be endemic among the Soweto
population. Case control studies all identified the same three environmental
factors in each disease: heavy alcohol consumption, marked exposure to
industrial chemicals and a low intake of fruit, which is a major source of
vitamin C.
Occupational health
People in various occupations may be exposed to xenobiotic substances that
have serious deleterious effects on health. It has been suggested that there is
an association between breast cancer and workshop exposure. The authors
believe that it is worth exploring exposure to chemicals metabolised
into reactive chemicals such as organic solvents and rubber and plastic
chemicals.13
Occupations cited as having possible links with chronic pancreatitis and
pancreatic cancer include employment in automobile engine and parts
manufacture, service and maintenance, as well as dry cleaning, catering,
cooking and serving, gasoline production, glue manufacture, oil refining,
petrochemical industries and steel manufacture.14
Exposure to low-dose ionising radiation
Imaging procedures are an important source of exposure to ionising radiation
and can result in high cumulative effective doses of radiation, which have
ly
been linked to the development of solid cancers and leukaemia. Thus the
on
growing use of medical imaging procedures has resulted in the risks of
radiation exposure becoming relevant.15
s
It has been reported that the per capita dose of radiation from medical
ge
imaging in the United States has increased by a factor of nearly six since
the early 1980s, the largest contributors to total effective doses being X-ray
pa
computed tomography (CT) scans and nuclear imaging, most of which
occurred in outpatient settings. The United States has the world’s highest per
e
capita imaging rate; as many as two per cent of cancers may be attributable
pl
to radiation exposure during CT scanning.
Radiation-induced cancer might not appear for years. While the danger
am
from individual scans may seem to be small, the effect is cumulative, so that
exposure to even moderate degrees of medical radiation is an important
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23. CHAPTER 2: A GLOBAL PHENOMENON: MEDICINE WITHOUT FRONTIERS 9
yet potentially avoidable public health threat—one should be aware of the
potential for radiation-induced carcinogenesis.16
Air pollution
Air pollution is an important cause of increased morbidity and mortality
worldwide. It has been suggested that sustained reduction of fine-particulate
air pollution exposure would result in improved life expectancy.17 K
CK FLIC
2
Dietary changes
UI
Western influences and modernisation of lifestyle in Asian populations has Q
resulted in an alarming increase in the prevalence of obesity, both in children
and adults.
Obesity
The health risks associated with increased prevalence of obesity, particularly
type 2 diabetes, have also shown a similar increase. Other diseases associated
with the obesity metabolic syndrome that have also indicated this pattern
include cardiovascular disease, hypertension, gallstones and certain cancers.
The health risks associated with obesity in Asian countries occur at a
lower body mass index (BMI) than that observed in Western populations.
This suggests that the current World Health Organization (WHO) criteria
for defining ‘overweight’ and ‘obese’ using BMI may not be appropriate for
some populations in the Western Pacific region. In addition, the pattern
of metabolic disease differs in Asians, who tend to preferentially increase
abdominal fat. Pacific Islanders tend to be prone to diabetes at greater
BMIs.
It is notable that obesity and under-nutrition occur side by side within the
same population in some developing countries. Specific populations affected
by the obesity epidemic include China, India, Japan, Korea, Malaysia,
Singapore, Taiwan, Thailand and the Philippines.18
ly
Junk food
on
There has been a marked increase in childhood obesity both in developed
and developing countries. Parallelling this has been a great increase of
s
food advertising in the media, particularly on television programs targeting
ge
children. Television has been singled out as the most easily modifiable
influential factor on diet. A survey carried out in six Asian nations—India,
pa
Indonesia, Malaysia, Pakistan, South Korea and the Philippines—showed,
for example, that 30 per cent of Malaysian children watch over eight hours
e
of television daily during holidays, exposing them to more than two and a
pl
half hours of advertisements a day. A similar trend, although not as marked,
was observed in the other countries surveyed; of these, only South Korea
am
and the Philippines have legislation regulating the advertising of fast food and
confectionery.
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24. 10 SECTION 1 | AN OVERVIEW
Child obesity has reached epidemic proportions in some countries and is
on the increase in others. Approximately 17.6 million children five years and
under are estimated to be overweight worldwide.
This trend has spread from the developed to the developing nations.
The long-term prognosis of this obesity epidemic is poor health with an
increased risk in adulthood of premature death from heart disease, and early
onset of diabetes and certain cancers. These can no longer be regarded
as Western diseases. A WHO report has emphasised that the incidence
of cardiovascular diseases has rapidly increased in India and China. The
incidence of diabetes is expected to rise 20 per cent worldwide over the next
two decades. This trend is partly due to obesity, unhealthy diets and sedentary
life styles. South-East Asia is witnessing the fastest spread of the epidemic. In
India and China the incidence is projected to rise by 50 per cent within the
next two decades, affecting younger people than in the developed countries.18
This trend is known as ‘the nutrition transition’. Interestingly, nutrition
problems in Asia cover the entire spectrum from diseases due to deficiency
to those due to excess. Global availability of cheap vegetable oils and fats has
resulted in greatly increased fat consumption among low-income nations. As the
nutrition transition has progressed, diets containing traditional root vegetables
and coarse grains are being replaced by refined rice and wheat along with other
food products containing a greater proportion of dietary fats and sweeteners.19
Television is the most powerful variable influencing child obesity,
contributing to it by two mechanisms: it reduces energy expenditure through
lowered physical activity at the same time as it increases dietary energy
intake, either during viewing or as a result of advertising. It has been observed
that the greater a child’s advertising exposure the more frequently snacking
occurs and the lower the child’s nutrient efficiency. Most food advertising
aimed at children is for foods and beverages high in sugars, fat and/or salt.
Exercise
ly
Many countries throughout the world are facing an increased incidence
on
of chronic diseases involving the cardiovascular, pulmonary and skeletal
systems, and cancer. Obesity and Type 2 diabetes are reaching epidemic
s
proportions. Regular exercise has been shown to reduce the risk for all of
ge
these diseases. It has been emphasised that regular physical activity has
numerous health benefits and is an essential component of a healthy lifestyle.
pa
Aerobic activity in particular brings about health benefits.19
The above is in the context of surveys that show that about 30 per cent
of Americans are inactive (sedentary) in their leisure time, approximately
e
pl
45 per cent are insufficiently active and only about 25 per cent are active at
recommended levels. Trends in leisure activity over time have been flat—
am
although there has been a gradual decline in the percentage of individuals
who are inactive and a greater decline in older age groups.20
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25. CHAPTER 2: A GLOBAL PHENOMENON: MEDICINE WITHOUT FRONTIERS 11
The recommended levels of exercise are at least 30 minutes of
moderate-intensity physical activity on five or more days each week. This
should be integrated into a ‘lifestyle intervention’ program that integrates
physical activity into daily life.21
A study by Lorig et al. (1999) has suggested that intervention is
feasible and beneficial beyond usual care in terms of improved health K
CK FLIC
status, and can decrease hospitalisation with a substantial savings in
health care cost.22 2
UI
Q
Summary
In conclusion, the breakdown of barriers to the spread of disease has
ramifications that impact on global health and may signal what one may
expect in the future. Awareness, adjustment and adaptability will be the key
to the practice of medicine worldwide.
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